PROCESS FOR THE PRODUCTION OF FIVE-MEMBERED OR SIX-MEMBERED CYCLIC ETHERS, IN PARTICULAR OF ANHYDROPOLYOLS

摘要

FIVE-MEMBERED OR SIX-MEMBERED CYCLIC ETHERS, IN PARTICULAR ANHYDROPOLYOLS, CAN BE OBTAINED BY CYCLODEHYDRATION OF POLYOLS HAVING AT LEAST 4 C ATOMS AND AT LEAST 2 HYDROXYL GROUPS IN THE PRESENCE OF WATER AND AN ACIDIC CATALYST. ACCORDING TO THE INVENTION THE CYCLODEHYDRATION IS PROMOTED AND THE FORMATION OF POLYMERS IS AVOIDED IF THE ACID-CATALYSED CYCLODEHYDRATION IS CARRIED OUT IN THE PRESENCE OF AN ACID-STABLE HYDROGENATING CATALYST IN A HYDROGEN ATMOSPHERE. ANHYDROHEXITOLS CAN BE OBTAINED BOTH FROM HEXITOLS AND FROM SUCROSE.